What it means
The position sensor reading does not transition cleanly between the two valve lift modes for actuator A on bank 2.
At a glance
- Usually lights the check-engine light
How it works
The A rocker arm position sensor on bank 2 tracks movement between the engine's valve-lift modes. This code sets when its reading does not follow the expected transition or travel, which can happen if the sensor has drifted or the mechanism's lock pin is worn.
Common causes
Most likely first.
- Sensor signal drift after thermal aging
- Worn lock pin reduces travel between modes
- Sensor element aged beyond calibration window
Symptoms
- Check-engine light
- Reduced engine power or performance
How to diagnose it
- Record freeze-frame data and compare live bank 2 A position readings with the commanded valve-lift mode, looking for a delayed, incomplete, or inconsistent transition.
- Inspect the A actuator sensor connector and bank 2 harness for looseness, corrosion, or damage that could distort the reading.
- Check the sensor supply, ground, and signal circuit against the manufacturer's specification to rule out wiring-related reading errors.
- Use the manufacturer's procedure to command the bank 2 A rocker arm between modes and observe whether the sensor tracks the movement smoothly.
- If the electrical circuit checks out, inspect the rocker arm mechanism and lock pin for wear or restricted travel.
Common fixes
- Repair a loose, corroded, or damaged bank 2 A sensor connector or wiring.
- Replace the bank 2 A position sensor if its output drifts outside the manufacturer's calibration range.
- Repair or replace the worn bank 2 A rocker arm lock pin or mechanism if it cannot complete its mode change.
Can I keep driving?
The engine may have reduced power because bank 2 A cannot reliably confirm its valve-lift mode. Drive gently and avoid hard acceleration until the actuator and sensor have been checked.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.